The Science Behind the Smoke: Incensole Acetate
For millennia, frankincense has been burned as incense in religious and cultural ceremonies, with anecdotal reports suggesting it promotes spiritual feelings, calmness, and mood elevation. Modern science began to provide a biological basis for these experiences in 2008 when an international team of scientists identified incensole acetate (IA) as a key psychoactive compound. IA is a diterpene found in the resin of some Boswellia species, such as B. papyrifera.
The researchers showed that when burned, IA is released in the smoke and can cross the blood-brain barrier in mice. Once in the brain, IA was found to activate specific ion channels called Transient Receptor Potential Vanilloid 3 (TRPV3). While TRPV3 channels are best known for their role in sensing warmth in the skin, they are also present in areas of the brain that regulate emotion. By activating these channels, incensole acetate produced significant antidepressant-like and anxiolytic (anti-anxiety) effects in the mice.
This finding provided a compelling explanation for the calming effects long associated with the ritual burning of frankincense. The study demonstrated that the psychoactive effect is not merely a product of scent or ritual but has a direct pharmacological mechanism.
Beyond the Aroma: The Role of Boswellic Acids
While inhalation leverages the volatile components like incensole acetate, oral ingestion of frankincense supplements focuses on a different class of compounds: boswellic acids. These triterpenoids are the primary active ingredients in standardized Boswellia extracts, such as those derived from B. serrata. Unlike incensole acetate, boswellic acids are not volatile and do not contribute to the psychoactive effects associated with inhaling frankincense smoke.
The primary effect of boswellic acids is potent anti-inflammatory activity. They work by inhibiting the enzyme 5-lipoxygenase (5-LOX), which is crucial for producing inflammatory leukotrienes. Neuroinflammation, or inflammation within the brain, is increasingly recognized as a contributing factor in mood disorders like depression and anxiety. Therefore, the anti-inflammatory action of boswellic acids, when taken orally, could indirectly influence mood by reducing neuroinflammation. This represents a separate, yet potentially complementary, pathway through which frankincense can affect the brain, depending on its form of use.
Frankincense and Neurological Function
Beyond anxiety and depression, research also suggests that frankincense and its compounds may support broader neurological and cognitive health, particularly in animal models.
- Memory and Learning: Studies have shown that frankincense extracts can enhance memory and learning capabilities in rats, especially in cases where cognitive function has been impaired by conditions like hepatic encephalopathy. The effect is linked to neuroprotective and anti-inflammatory properties that reduce neuronal cell death and increase connections within the hippocampus, a brain region critical for memory formation.
- Neuroprotection: Specific boswellic acids, including 3-O-acetyl-11-keto-β-boswellic acid (AKBA), have demonstrated neuroprotective effects by reducing oxidative stress and inhibiting cell apoptosis. This is particularly relevant for neurodegenerative conditions like Parkinson's and Alzheimer's disease, though human data is still limited.
- Brain Tumor-Related Edema: Some research has indicated that oral Boswellia extract may help reduce brain edema (swelling) associated with malignant gliomas, though it does not reduce the tumor size itself. This effect is likely mediated by the anti-inflammatory properties of boswellic acids.
How Frankincense Compounds Interact with the Brain
Different compounds in frankincense employ distinct mechanisms to influence the central nervous system:
- Incensole Acetate (IA): Primarily associated with inhalation (e.g., from incense smoke or certain essential oils). It activates TRPV3 ion channels in the brain, which are linked to emotional regulation. IA may also modulate the hypothalamic-pituitary-adrenal (HPA) axis, the body's central stress response system.
- Boswellic Acids (BAs): Found in oral supplements (e.g., Boswellia serrata extracts). Their anti-inflammatory action reduces neuroinflammation, which is implicated in mood disorders. One specific acid, AKBA, has been studied for potential antidepressant-like effects in animal models.
- Terpenes (e.g., alpha-pinene): These volatile compounds, present in the essential oil, can be inhaled and interact with the olfactory-limbic system connection. Alpha-pinene has shown anti-anxiety and antidepressant-like effects in animal studies, potentially by modulating the GABAergic system.
Navigating Forms: Inhaled vs. Oral Frankincense
When considering the effects of frankincense, it's crucial to understand the differences between the forms available. The distinction between inhaling the volatile components and ingesting the non-volatile ones dictates the potential pharmacological effects.
| Feature | Inhaled (Essential Oil, Incense) | Oral (Boswellia Extract Supplements) |
|---|---|---|
| Primary Active Compounds | Incensole Acetate, Volatile Terpenes (e.g., alpha-pinene) | Boswellic Acids (e.g., AKBA, KBA) |
| Method of Absorption | Inhalation of vapor or smoke. Olfactory-limbic pathway and absorption into the bloodstream. | Oral ingestion, absorption through the digestive tract. |
| Primary Mechanism | Psychoactive effects mediated by TRPV3 channel activation and interaction with emotional centers of the brain. | Anti-inflammatory effects by inhibiting 5-lipoxygenase, reducing systemic and neuroinflammation. |
| Effect on Mood | Potential for rapid calming, anti-anxiety, and antidepressant-like effects (animal studies). | Indirect mood benefit via reduction of inflammation. Slower onset of action. |
Is Frankincense Safe? Considerations and Precautions
While frankincense has a long history of use and is generally considered low-toxicity, certain risks and considerations exist, especially with different forms of administration.
Potential Side Effects
- Skin Irritation: Applying undiluted frankincense essential oil directly to the skin can cause irritation or allergic reactions in some individuals. It should always be diluted with a carrier oil like jojoba or almond oil.
- Gastrointestinal Distress: Oral frankincense supplements, particularly in high doses, can cause mild side effects like indigestion, nausea, or constipation.
- Internal Use of Essential Oils: Ingestion of frankincense essential oil is generally not recommended and should only be done under strict medical supervision. There are no standard regulations for essential oils sold for internal use, and some may contain unsafe ingredients.
Drug Interactions and Contraindications
- Blood Thinners: Frankincense may possess blood-thinning properties. Individuals taking anticoagulant medications like warfarin should consult a doctor before using frankincense, as it could increase the risk of bleeding.
- Pregnancy: Due to its potential emmenagogue properties (promoting menstrual flow), frankincense is often advised against during pregnancy as it may be hazardous to the fetus.
- NSAIDs: Some sources suggest potential interactions between frankincense (particularly oral supplements) and nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen.
Status of Human Clinical Evidence
It is important to note that much of the compelling evidence for frankincense's psychoactive and neuroprotective effects comes from preclinical studies using animal models. While these findings offer valuable insights, robust, high-quality human clinical trials confirming these specific benefits for mood, anxiety, and cognition are limited. More research is needed to determine efficacy, optimal dosages, and long-term safety in human populations. Individuals should consult with a healthcare professional before using frankincense therapeutically.
Conclusion: A Nuanced Answer
Yes, certain components of frankincense are indeed psychoactive, but the answer is nuanced and depends on the form of use. The inhalation of burned frankincense, particularly from species containing incensole acetate, has been shown to produce mild psychoactive effects in animal studies, with a direct mechanism involving the activation of brain-based TRPV3 channels. In contrast, oral frankincense extracts containing boswellic acids primarily exert systemic anti-inflammatory effects that may indirectly benefit mood by reducing neuroinflammation. Both forms also show promise for neuroprotective and cognitive-enhancing properties, though more human clinical research is needed to confirm these findings. The centuries-old use of frankincense for spiritual and emotional well-being is now supported by emerging scientific evidence, though practical application should proceed with awareness of the different pharmacological effects and necessary safety precautions.
Visit PubMed Central for more research on Frankincense and its effects.
